Q. I have a problem that is...

Q. I have a problem that is causing me much anguish. When I try to stand after sitting for a spell, or get out of bed swiftly in the morning, I become very dizzy and feel very faint. This has just started within the last month or so, and I don't want to go on like this for much longer. What's the cause and what's the cure? I'll bet you know something that can help me and would be most grateful for your reply.

A. The general medical term that describes your condition is syncope. Sometimes called swooning and a kin to fainting, syncope is a common condition and a frequent cause of concern. It occurs when the flow of blood, with its precious cargo of oxygen, is reduced suddenly, usually as a result of an abrupt fall in the blood pressure.

When you rise suddenly after a period of rest, the force of gravity pulls your blood down into your legs and reduces the amount of blood returning to the heart, decreasing the blood pressure and the amount of blood the heart can pump to the brain and other parts of the body. Without the needed supply of oxygen, the brain cannot function and the person faints and falls to the floor, which usually places the head (and the brain) on a level even with the heart and effectively restores the balance of blood flow.

If blood pressure falls only when a person assumes an erect position from a sitting or reclining attitude, it may also be called orthostatic hypotension. And that can result from a number of causes, but especially as the result of certain medications.

Have you recently started a new blood pressure medication, or a water pill (diuretic) for edema or leg swelling? In fact, have you started any new medication lately? This would be my first line of investigation into your problem, and I think the odds are in favor of finding there the reasons for your condition. There are other reasons, of course, neurological disorders that must be considered, but they are less common.

Until you do find the cause, you must learn to arise carefully, first sitting up in bed for a while, then letting your feet dangle over the side of the bed before standing erect. This slow pace will allow your heart to make the changes necessary to keep your blood flowing to the brain by increasing the strength and speed of its beat.

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